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A.S. Kumar et al. / European Journal of Medicinal Chemistry 60 (2013) 305e324
84% yield. Liquid IR (neat): 2931, 2852, 1595, 1484, 1331, 1137, 1071,
914, 802, 768 cmꢁ1. 1H NMR (300 MHz, CDCl3):
3.59 (s, 3H), 3.88
5.1.4.7. 40-Chloro-2,3,4-trimethoxy-6-vinylbiphenyl (18g).
d
(s, 3H), 3.93 (s, 3H), 5.09 (d, 1H, J ¼ 10.9 Hz), 5.52 (d, 1H, J ¼ 17.3 Hz),
6.35 (dd, 1H, J ¼ 10.9 Hz, 17.3 Hz), 6.86 (s, 1H), 6.88e6.99 (m, 1H),
7.00e7.22 (m, 2H). 13C NMR (75 MHz, CDCl3):
d 55.9, 60.8, 60.9,
104.1, 114.4, 116.4, 119.6, 126.2, 127.0, 132.1, 132.9, 135.0, 142.1, 147.7,
148.1, 151.1, 153.1. ESI MS (m/z): 329 (M þ Na)þ.
Following the general procedure B, compound 18g was purified
by column chromatography, eluting with hexaneeEtOAc (9.2:0.8).
86% yield. Liquid. IR (neat): 2936, 2834, 1590, 1478, 1328, 1093, 916,
5.1.4.4. 2,3,4-Trimethoxy-6-vinylbiphenyl (18d).
816, 764 cmꢁ1 1H NMR (300 MHz, CDCl3):
. d 3.55 (s, 3H), 3.88 (s,
3H), 3.93 (s, 3H), 5.06 (d, 1H, J ¼ 10.8 Hz), 5.51 (d, 1H, J ¼ 17.3 Hz),
6.36 (dd,1H, J ¼ 10.8 Hz,17.3 Hz), 6.87 (s,1H), 7.15 (d, 2H, J ¼ 8.3 Hz),
7.35 (d, 2H, J ¼ 8.3 Hz). 13C NMR (75 MHz, CDCl3):
d 55.9, 60.7, 60.8,
104.1, 114.0, 127.1, 128.0, 132.0, 132.1, 132.9, 134.5, 135.3, 142.2, 151.2,
152.9. ESI MS (m/z): 305 (M þ H)þ.
Following the general procedure B, compound 18d was purified
by column chromatography, eluting with hexaneeEtOAc (9.7:0.3).
83% yield. White solid. mp. 64e66 ꢀC. IR (KBr): 2972, 2854, 1596,
1449, 1329, 1148, 1095, 846, 708 cmꢁ1. 1H NMR (300 MHz, CDCl3):
5.1.4.8. 40-Fluoro-2,3,4-trimethoxy-30-methyl-6-vinylbiphenyl (18h).
d
3.54 (s, 3H), 3.89 (s, 3H), 3.93 (s, 3H), 5.04 (d, 1H, J ¼ 10.5 Hz), 5.50
(d, 1H, J ¼ 17.3 Hz), 6.38 (dd, 1H, J ¼ 10.5 Hz, 17.3 Hz), 6.89 (s, 1H),
7.15e7.23 (m, 2H), 7.28e7.41 (m, 3H). 13C NMR (75 MHz, CDCl3):
d
55.9, 60.8, 60.9, 103.8, 113.6, 126.8, 127.7, 128.6130.6, 131.9, 135.4,
136.1, 142.1, 151.2, 152.7. ESI MS (m/z): 271 (M þ H)þ.
5.1.4.5. 40-tert-Butyl-2,3,4-trimethoxy-6-vinylbiphenyl (18e).
Following the general procedure B, compound 18h was purified
by column chromatography, eluting with hexaneeEtOAc (9.7:0.3).
82% yield. Liquid. IR (neat): 2926, 2851, 1589, 1482, 1328, 1136, 1093,
990, 801, 754 cmꢁ1. 1H NMR (300 MHz, CDCl3):
d 2.30 (s, 3H), 3.60
(s, 3H), 3.91 (s, 3H), 3.94 (s, 3H), 5.09 (d, 1H, J ¼ 10.9 Hz), 5.56 (d, 1H,
J ¼ 17.5 Hz), 6.41 (dd,1H, J ¼ 10.9 Hz,17.5 Hz), 6.94 (s,1H), 6.99e7.08
(m, 3H). 13C NMR (75 MHz, CDCl3):
d 14.5, 55.9, 60.8, 60.9, 103.7,
113.7, 114.4, 124.0,127.6, 129.5, 131.5, 132.0, 133.6, 135.2, 142.0, 151.2,
152.7, 162.0. ESI MS (m/z): 303 (M þ H)þ.
5.1.4.9. 2,3,30,4,40-Pentamethoxy-6-vinylbiphenyl (18i).
FollowingthegeneralprocedureB, compound 18e was purifiedby
column chromatography, eluting with hexaneeEtOAc (9.7:0.3). 85%
yield. White solid. mp. 61e63 ꢀC. IR (KBr): 2959, 2866, 1589, 1480,
1327, 1146, 1088, 926, 815 cmꢁ1. 1H NMR (300 MHz, CDCl3):
d 1.38 (s,
9H), 3.56 (s, 3H), 3.89 (s, 3H), 3.93 (s, 3H), 5.04 (d,1H, J ¼ 11.1 Hz), 5.50
(d,1H,J¼ 17.1 Hz), 6.41(dd,1H,J¼ 11.1Hz,17.1 Hz), 6.89(s,1H), 7.11 (d,
2H,J¼ 8.1Hz), 7.36 (d, 2H,J¼ 8.1Hz).13CNMR(75 MHz, CDCl3):
d31.5,
34.6, 55.9, 60.8, 103.9, 113.2, 124.6, 128.6, 130.3, 132.1, 133.0, 135.8,
142.2, 149.4, 151.1, 152.6. ESI MS (m/z): 327 (M þ H)þ.
Following the general procedure B, compound 18i was purified
by column chromatography, eluting with hexaneeEtOAc (9.2:0.8).
81% yield. White solid. mp. 83e85 ꢀC. IR (KBr): 2933, 2835, 1587,
1484, 1246, 1140, 1096, 1922, 798 cmꢁ1. 1H NMR (300 MHz, CDCl3):
5.1.4.6. 2-(2,3,4-Trimethoxy-6-vinylbiphenyl)naphthalene
(18f).
d
3.56 (s, 3H), 3.86 (s, 3H), 3.89 (s, 3H), 3.91 (s, 3H), 3.92 (s, 3H), 5.04
(d,1H, J ¼ 10.8 Hz), 5.49 (d,1H, J ¼ 17.8 Hz), 6.43 (dd, 1H, J ¼ 10.8 Hz,
17.8 Hz), 6.71e6.75 (m, 2H), 6.84e6.88 (m, 2H). 13C NMR (75 MHz,
CDCl3):
d 55.7, 55.9, 60.9, 103.8, 110.5, 113.4, 119.4, 122.9, 128.2,
128.4, 132.1, 135.4, 142.0, 147.8, 148.1, 151.1, 152.5. ESI MS (m/z): 353
(M þ Na)þ.
Following the general procedure B, compound 18f was purified
by column chromatography, eluting with hexaneeEtOAc (9.2:0.8).
83% yield. White solid. mp. 67e69 ꢀC. IR (KBr): 2926, 1658, 1548,
1431, 1354, 1199, 1086, 931, 746 cmꢁ1. 1H NMR (300 MHz, CDCl3):
5.1.5. General procedure C for the synthesis of stilbenes (19aek)
Taken the aryl halide (1.0 equiv), and styrene (1.2 equiv) into
3 ml of DMA in a 50 mL round bottom flask, then added 0.05 mol%
Pd(OAc)2 and 1.4 equiv of K3PO4 and the reaction mixture was
subjected to reflux at 140 ꢀC for 12 h [15]. After the completion of
the reaction, reaction mixture was extracted with ethyl acetate
(3 ꢃ 10 mL), the organics were washed with water (2 ꢃ 10 mL), and
dried over anhydrous sodium sulfate. The solvent was evaporated,
and the residue was purified by column chromatography on silica
gel, eluting with hexane/EtOAc mixture and it is observed that
d
3.54 (s, 3H), 3.91 (s, 3H), 3.95 (s, 3H), 5.02 (d, 1H, J ¼ 10.9 Hz), 5.53
(d, 1H, J ¼ 17.3 Hz), 6.41 (dd, 1H, J ¼ 10.9 Hz, 17.3 Hz), 6.93 (s, 1H),
7.32e7.39 (m, 1H), 7.40e7.51 (m, 2H), 7.66 (s, 1H), 7.76e7.89 (m,
3H). 13C NMR (75 MHz, CDCl3):
d 55.9, 60.7, 60.9, 104.3, 113.6, 125.8,
127.1, 127.7, 128.0, 128.5, 129.1, 129.2, 132.2, 132.5, 133.2, 133.7, 135.7,
142.4, 151.6, 152.9. ESI MS (m/z): 343 (M þ Na)þ.